Approved for the App Store. €0.99 once in Italy; the store page is still becoming available.
Heremin
A theremin on your Apple Watch, the electronic instrument you play without touching it. The sound comes from the Watch speaker; your arm is the instrument.
Raise your forearm for higher notes: three octaves, gliding from one note to the next.
Roll your wrist to set the volume, swing your arm sideways to change the sound from a pure sine to a square wave, or set it with a knob.
With an iPhone that has Ultra Wideband, the iPhone becomes the antenna: move your wrist closer for higher notes.
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